******************************************************************** *** Atmospheric CO2-curve values (ppmv) derived from flask air *** *** samples collected at Cape Kumukahi, Hawaii *** *** *** *** Source: R. F. Keeling, S. C. Piper, A. F. Bollenbacher *** *** and S. J. Walker *** *** Carbon Dioxide Research Group *** *** Scripps Institution of Oceanography (SIO) *** *** University of California *** *** La Jolla, California USA 92093-0444 *** *** *** *** May 2008 *** ******************************************************************** Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann. Ave. 1979 339.54 340.56 341.25 340.16 337.58 334.98 333.96 335.06 337.01 338.34 1980 339.44 340.41 341.07 342.02 342.62 341.41 338.77 336.13 335.12 336.22 338.17 339.49 339.24 1981 340.59 341.55 342.18 343.12 343.73 342.55 339.90 337.24 336.20 337.30 339.26 340.59 340.35 1982 341.69 342.65 343.26 344.19 344.78 343.56 340.85 338.13 337.03 338.11 340.07 341.44 341.31 1983 342.60 343.64 344.36 345.41 346.12 345.03 342.44 339.84 338.87 340.06 342.11 343.54 342.84 1984 344.72 345.75 346.45 347.44 348.06 346.83 344.13 341.43 340.38 341.49 343.47 344.84 344.58 1985 345.99 347.01 347.70 348.71 349.39 348.22 345.53 342.81 341.72 342.82 344.80 346.16 345.91 1986 347.31 348.34 349.04 350.09 350.81 349.71 347.09 344.43 343.41 344.56 346.59 347.97 347.45 1987 349.13 350.16 350.87 351.92 352.64 351.53 348.91 346.27 345.29 346.51 348.62 350.10 349.33 1988 351.35 352.48 353.28 354.40 355.13 353.99 351.34 348.67 347.64 348.77 350.76 352.10 351.66 1989 353.22 354.21 354.87 355.89 356.56 355.39 352.70 349.98 348.94 350.12 352.20 353.64 353.14 1990 354.85 355.92 356.62 357.67 358.36 357.20 354.49 351.75 350.67 351.80 353.82 355.20 354.86 1991 356.34 357.35 358.01 359.00 359.64 358.40 355.61 352.79 351.66 352.75 354.75 356.10 356.03 1992 357.22 358.20 358.84 359.80 360.37 359.05 356.21 353.38 352.25 353.35 355.34 356.68 356.72 1993 357.80 358.77 359.41 360.39 361.03 359.79 357.01 354.23 353.15 354.34 356.45 357.93 357.53 1994 359.16 360.25 360.97 362.04 362.75 361.58 358.86 356.12 355.09 356.32 358.46 359.93 359.29 1995 361.15 362.21 362.91 363.95 364.64 363.44 360.68 357.91 356.86 358.07 360.19 361.66 361.14 1996 362.88 363.97 364.72 365.81 366.51 365.28 362.51 359.73 358.65 359.82 361.88 363.28 362.92 1997 364.43 365.44 366.10 367.12 367.80 366.58 363.80 361.02 359.99 361.27 363.50 365.09 364.35 1998 366.43 367.63 368.44 369.60 370.39 369.25 366.54 363.80 362.79 364.05 366.22 367.69 366.90 1999 368.90 369.93 370.58 371.56 372.17 370.85 367.95 365.05 363.92 365.13 367.28 368.79 368.51 2000 370.05 371.17 371.94 373.04 373.73 372.48 369.65 366.84 365.77 367.00 369.14 370.61 370.12 2001 371.84 372.91 373.60 374.64 375.31 374.03 371.15 368.27 367.14 368.35 370.49 371.97 371.64 2002 373.21 374.30 375.02 376.10 376.83 375.62 372.83 370.04 369.03 370.37 372.67 374.28 373.36 2003 375.63 376.83 377.62 378.77 379.53 378.32 375.48 372.61 371.51 372.76 374.96 376.47 375.87 2004 377.74 378.87 379.65 380.79 381.52 380.29 377.46 374.64 373.59 374.87 377.08 378.60 377.93 2005 379.88 381.01 381.77 382.88 383.63 382.40 379.55 376.69 375.63 376.94 379.21 380.80 380.03 2006 382.15 383.34 384.13 385.27 386.02 384.76 381.83 378.87 377.68 378.87 381.02 382.50 382.20 2007 383.74 384.85 385.59 386.72 387.49 386.28 383.43 380.55 379.46 380.73 382.95 384.47 383.86 Values above are taken from a curve consisting of 4 harmonics plus a stiff spline and a linear gain factor, fit to monthly concentration values adjusted to represent 2400 hours on the 15th day of each month. Data used to derive this curve are shown in the accompanying graph. Units are parts per million by volume (ppmv) expressed in the 2003A SIO manometric mole fraction scale. The "annual average" is the arithmetic mean of the twelve monthly values.